The blue color is more likely to be visible because blue light is on the short wavelength end of the color spectrum. A budweiser can would have appeared to have gray ink instead of red - because that color is at the long wavelength end of the spectrum.
For a given water condition, colors on the red end of the spectrum "go gray" more rapidly than colors at the opposite end of the spectrum. Sunlight angle, haze/clouds, dust, and other atmospheric variables will affect the result. Algae, sediment, and other things that affect the appearance of the water also affect the color spectrum absorption. (You're getting this from a divemaster with over 1000 dives from 10-130 feet.)
I used to take a dive light on 60' dives during the day just to turn it on to show clients the true colors of the reef. Without the light, "color" was relative - lots of varying grays and muted drab colors with the dive light off.